An investigation of iodine nutrition and thyroid function in downtown residents of Longyan city, Fujian province / 中国地方病学杂志

ABSTRACT

Objective To find out the iodine nutritional status of Longyan downtown residents,evaluate the effectiveness of control measures and provide a scientific basis for developing control strategies.Methods Infants aged 0 to 2 year-old,children aged 8 to 10,adults aged 18 to 45 and pregnant and lactating women were selected as survey subjects.Children goiter was detected with B ultrasound.Residents per capita daily salt intake was investigated by weighing method.Three urinary samples and a milk sample of lactating women were randomly collected.Urinary iodine and milk iodine content were determined by arsenic cerium catalytic spectrophotometric assay.Blood samples were collected and thyroid function (including serum TT3,FT3,TT4 and FT4) and thyroid stimulating hormone(TSH) were measured with direct chemiluminescence immunoassay,and thyroglobulin antibody(TgAb),thyromicrosome antibody(TMAb),and thyroglobulin (Tg) were measured with radioimmunoassay (RIA) in serum.ResultsThe goiter rate of children aged 8 to 10 was 1.8％ (2/110),and median thyroid volume was 2.75 ml.Household iodized salt coverage rate was 100.00％(318/318),and qualified iodized salt was 94.03％ (299/318).The daily per capita salt intake was (6.13 ± 3.56)g.The average medians of urinary iodine of the infants,children,adults,pregnant and lactating women were 181.8,315.2,196.6,158.7,136.4 μg/L,respectively.The median of milk iodine of lactating women was 155.6 μg/L.The proportions of serum TT3,FT3,TT4,FT4 and TSH which higher than normal were 3.6％ (11/308),0.6％ (2/309),23％ (7/309),1.0％ (3/313) and 1.3％ (4/312),respectively.While the proportions of serum TT3,FT3,TT4,FT4 and TSH that lower than normal were 2.3％ (7/308),11.7％(36/309),2.3％(7/309),12.8％(40/313),and 1.6％(5/312),respectively,of which 16 cases of both TgAb and TMAb were higher than normal.ConclusionsExisting salt iodine level is appropriate for 0 to 2 year-old infants and young children,18 to 45 year-old adults,pregnant and lactating women in downtown Longyan city.The iodine intake of children aged 8 to 10 is excessive.Thyroid function monitoring is recommended to be included in the routine monitoring.